Oh, and I should say the function I want to implement is getFontBBox :: Font -> String -> IO [Float]
I do know how to marhsal/unmarshal the String. Just not the CFloat array to Haskell [Float] On Fri, Jun 20, 2008 at 2:25 PM, Jefferson Heard < [EMAIL PROTECTED]> wrote: > Well, Achim you were almost exactly correct. I have a functional function > interface in about half an hour's worth of work. I have one question, which > is how to create a Ptr to four CFloats on the fly, pass them to the bounding > box functions, and then come back out with a [Float] > > My prototype looks like this: > foreign import ccall unsafe "ftglGetFontBBox" fgetFontBBox :: Font -> > CString -> Ptr CFloat -> IO () > > the ptr to cfloat should be a float[4], which is modified inside the > original C function. > > > On Fri, Jun 20, 2008 at 1:16 AM, Achim Schneider <[EMAIL PROTECTED]> wrote: > >> "Jefferson Heard" <[EMAIL PROTECTED]> wrote: >> >> > I've been looking for awhile now for a simple way to get truetype >> > fonts into my visualizations so I can abandon the hideous GLUT fonts >> > and make things that look like they were developed in the 1990s >> > instead of back in the days of TRON. I found FTGL, but I'm mostly a >> > Haskell developer these days, and resent having to go back to C just >> > to write a simple application. >> > >> > So I was wondering if anyone had ever wrapped the FTGL library in >> > Haskel FFI or whether those out there who are experts on the FFI >> > think at first glance it should be readily wrappable by a rank >> > amateur at FFI such as myself. >> > >> > http://ftgl.sourceforge.net/docs/html/ >> > >> Using the FFI is generally straight forward, as long as you can live >> with using the IO monad and the C code uses objects (well, >> pointers to structs passed as first argument, where's the >> difference...). >> >> Things only depend on the purity of the C code and how high-level you >> want your interface to be. In this case, I estimate half an hour if >> you're a fast typist. That includes the time needed to read the FFI >> docs. >> >> -- >> (c) this sig last receiving data processing entity. Inspect headers for >> past copyright information. All rights reserved. Unauthorised copying, >> hiring, renting, public performance and/or broadcasting of this >> signature prohibited. >> >> _______________________________________________ >> Haskell-Cafe mailing list >> Haskell-Cafe@haskell.org >> http://www.haskell.org/mailman/listinfo/haskell-cafe >> > > > > -- > I try to take things like a crow; war and chaos don't always ruin a picnic, > they just mean you have to be careful what you swallow. > > -- Jessica Edwards -- I try to take things like a crow; war and chaos don't always ruin a picnic, they just mean you have to be careful what you swallow. -- Jessica Edwards
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